The present invention relates to an optical disk memory device.
Recently, an image information filing apparatus has been developed in which a document or the like is two-dimensionally scanned by a light beam; the image information from this document is converted to an electrical signal; the image data obtained in this way is stored; and the stored image data can be searched and reproduced as necessary. In this kind of image information filing apparatus, an optical disk memory is used as an image memory to store the image data. In this kind of optical disk memory, information is stored on, for example, spiral or coaxial tracks by means of an optical head which rectilinearly moves in the radial direction of this optical disk memory. To determine the memory locations in the optical disk memory, the spiral or coaxial tracks are divided for every block having a fixed data length. A block of address data is preliminarily stored in the head of each block. In this kind of optical disk memory, for example, in the case of reading out data from a desired block, the optical head is accessed near this block and the designated block is detected while reading the track number and block number stored in this accessed region. In this case, when it is assumed that, for instance, the block in the innermost track is designated, there is a possibility that the optical head will search the region (the furthest inner region on the innermost track) where the block number, track number, etc. are not stored. In such a case, obviously, the track number and block number cannot be read out, which causes a problem in that the designated block cannot be accurately detected.